1. The problem statement, all variables and given/known data I'm given a relativistic Boltzmann gas and told to find the entropy 2. Relevant equations [tex]\epsilon = pc[/tex] p = 3d momentum c = speed of light 3. The attempt at a solution I tried to start by finding the partition function, from which I can just take the derivative, but I don't know how I would sum the energies. Would I merely use p=hw/2*pi summed over all frequencies from 0 to infinity?